1. Field of the Invention
The present invention relates to a modular jack mounted to an apparatus such as a notebook type personal computer, a game machine or the like and mated with a modular plug corresponding thereto.
2. Description of the Related Art
According to a modular jack of this kind, a surrounding of a casing made of synthetic resin is covered by a shell made of metal for electromagnetic shielding.
Normally, the shell is formed by pressing a sheet metal member. The shell is provided with a front plate constituting a square ring shape covering a front plate of a casing and side plates covering respective side walls of the casing. Further, reinforcement tabs extended along a conductive portion on a printed wiring board are respectively extended integrally from a pair of the opposed side plates of the shell and the respective reinforcement tabs are fixed to the conductive portion by soldering.
In this way, the conventional shell is constructed by a comparatively complicated structure integrally provided with the reinforcement tabs and therefore, there is a drawback described below.
That is, the shell is, for example, plated with tin for rust prevention. When the shell having the above-described integrated structure is assumedly formed by pressing after plating the sheet metal member (That is, a case of so-to-speak previous plating), a rupture face by pressing is exposed at a portion of the reinforcement tab. The plating is not carried out at the portion and therefore, there is a concern that wettability of solder is poor and fixing by soldering becomes uncertain.
Conversely, when pressing is carried out previously and plating is carried out by dipping a complicated structure integrally formed with the shell and the reinforcement tabs into a plating tank (That is, a case of so-to-speak post plating), there is a concern that the shells having the complicated structure are tangled with each other and deformed. When the plating step is going to be carried out such that the above-described situation is avoided, operational efficiency is deteriorated and fabrication cost is increased.
The invention has been carried out in view of the above-described problem and it is an object of the invention to provide a modular jack which is fixed to a printed wiring board with certainty and inexpensive.
In order to achieve the above-described object, according to a first aspect of the invention, there is provided a modular jack characterized in including: a casing having an insulating performance arranged above a printed wiring board; a shell made of metal for electromagnetic shielding covering at least a portion of the casing; and a reinforcement tab made of metal and provided separately from the shell for fixing the casing onto the printed wiring board, wherein the reinforcement tab includes a side plate fixed to a side wall of the casing and engaged with a side wall of the shell and a leg portion extended from the side plate along a surface of the printed wiring board and soldered to a conductive portion of the surface of the printed wiring board, and wherein the side wall of the shell and the side plate of the reinforcement tab are electrically conducted via an engaging portion, and wherein the reinforcement tab is constituted by coating a surface of a pressed product with a conductive plated coating.
According to the invention, the reinforcement tab can be constituted by a part having a simple structure separately from the shell and therefore, even when plating is carried out after pressing (post plating), pressed products are not tangled with each other in a plating tank, therefore, so-to-speak post plating can be carried out without lowering operational efficiency in plating. By carrying out the post plating, rupture face in pressing is coated by the plated coating and therefore, as a result of improving wettability of solder of the portion, the reinforcement tab is fixed with certainty. Further, the shell and the reinforcement tab are engaged with each other to thereby ensure electric conduction and therefore, for example, when the shell is connected to a chassis of an apparatus and the reinforcement tab is connected to the printed wiring board, a ground through path for matching levels of the chassis and the printed wiring board can be achieved by a simple structure by way of the shell and the reinforcement tab. Further, the shell can also be prevented from being drawn from the casing by the reinforcement tab.
According to a second aspect of the invention, there is provided the modular jack according the first aspect, characterized in that the engaging portion includes an engaging projected portion formed at either one of the side wall of the shell and the side plate of the reinforcement tab and engaged with the other thereof to thereby prevent the shell from being detached from the casing. According to the invention, the shell can be prevented from being detached with certainty.
According to a third aspect of the invention, there is provided the modular jack according to the first or second aspect, characterized in that the shell includes the side wall having an elastic piece for grounding. According to the invention, for example, when the modular jack is set to a containing recessed portion of the apparatus, the elastic piece is brought into elastic contact with a predetermined contact portion in the containing recess portion and contact for grounding can easily be constituted.